There are electrical contacts through a wafer or through a subarea of a wafer in greatly varying embodiments. These through contacts are becoming increasingly significant. If multiple components are placed vertically one on top of another, very beneficial and small-dimensioned arrangements may be obtained by integrating electrical through contacts into the component.
A micromechanical component is discussed in German patent document DE 10 2007 059 337 A1, which has multiple through contacts, in order to be able to interconnect the micromechanical component with another micromechanical component, for example.
As described in greater detail hereafter on the basis of FIGS. 1a and 1b and 1c, undesired effects occur during the etching of trenches in a substrate. Thus, because of the ARDE effect, trenches having different widths may not be etched to the same depth without a corresponding stop layer in a substrate. Furthermore, etching rate differences may occur, in the case of which the etching speed is accelerated at an edge of the substrate, for example. This effect is described as the so-called wafer edge effect.